BinUtils: Avoid llvm-strip versions older than Clang 11
Since !6164 (merged) we correctly prefer the more-specific name
llvm-strip
over strip
when using Clang. However, llvm-strip
from Clang versions prior to 11 require extra flags to strip everything.
Until our install(TARGETS)
logic learns to add those flags, avoid
using older versions of llvm-strip
by default.
Fixes: #22785 (closed)
Backport: release